Accurate, High Resolution 3D Dosimetry

描述（由申请人提供）：放射物理中心（RPC）最近的一份报告显示，38%的机构在第一次尝试时未能通过头颈部IMRT体模认证测试。确定了各种各样的失败原因。该报告提供的证据表明，调强放射治疗的实施是不平凡的，容易出错，患者的治疗可能会因此受到影响。真正实用的3D剂量测定系统将通过在调试和常规QA期间进行全面的剂量测定验证来解决这些故障的根本原因。该提案将进一步开发临床可行的3D剂量测定系统，并在患者队列中对IMRT输送中的剂量测定准确性进行首次全面的3D调查。我们之前的研究已经证明，一种新的PRESAGE/光学CT系统可以执行准确和高分辨率的3D剂量测定，并具有关键的优势，替代方法。这些包括更高的精度、更低的噪声、消除主要的伪影来源（散射和边缘效应）以及更高的实用性（对实验室/临床环境的鲁棒性、稳定性、可加工性等）。这些优点使PRESAGE/光学CT系统成为未来可行的3D剂量测定系统。我们建议建立一个强大的三方联盟，以实现两个主要目标：一个持续的技术和研究目标，以及一个新的临床应用目标。该联盟将3D剂量测定（杜克）方面的杰出专业知识与认证经验（RPC）和材料专业知识（Rider）相结合。其目的是平衡研究创新，以促进非专业诊所的3D剂量测定，同时仍然解决使用更专业的系统进行详细的临床IMRT剂量测定研究的迫切需要。我们假设新型光学CT扫描系统和新型辐射变色制剂将在不影响准确性的情况下实现速度和实用性的大幅提高。我们还假设，3D剂量测定技术将检测到更多的临床IMRT交付失败的标准比较指标，比传统的2D技术。该提案将对关键临床部位（骨盆、头颈部和胸部）患者队列中IMRT输送的准确性进行首次全面的3D调查。成功完成将提升先进放射治疗验证的最新技术水平，并可能证明强大而全面的新3D认证技术的可行性，该技术有可能提高临床试验的实践标准。迫切需要提高先进放射治疗的准确性。我们调查了一个三维剂量测定系统，将解决这一需要，促进剂量误差检测。将对3D患者治疗中剂量测定的准确性进行首次全面调查。

DESCRIPTION (provided by applicant): A recent report from the Radiological Physics Center (RPC) revealed that 38% of institutions failed the head- and-neck IMRT phantom credentialing test at the first attempt. A wide variety of causes for failure were identified. The report provides evidence that IMRT implementation is non-trivial and prone to error, and that patient treatment may be compromised as a result. A truly practical 3D dosimetry system would address a root cause of these failures, by enabling comprehensive dosimetric verification during commissioning and routine QA. This proposal will further develop a clinically viable 3D dosimetry system and conduct the first comprehensive 3D investigations of the accuracy of dosimetry in IMRT delivery, in patient cohorts. Our prior research has demonstrated that a new PRESAGE/optical-CT system can perform accurate and high- resolution 3D dosimetry, and has critical advantages over alternative approaches. These include substantially greater accuracy, lower noise, elimination of major sources of artifacts (scatter and edge effects), and improved practicality (robustness to lab/clinical environment, stability, machineability etc). These advantages render the PRESAGE/Optical-CT system a viable 3D dosimetry system for the future. We propose a strong 3- party consortium to pursue two major aims; a continued technical and investigational aim, and a new clinical applications aim. The consortium combines outstanding expertise in 3D dosimetry (Duke) with credentialing experience (RPC), and materials expertise (Rider). The aims balance investigating innovations to facilitate 3D dosimetry for the non-specialized clinic, while still addressing the urgent need for detailed clinical IMRT dosimetry studies using a more specialized system. We hypothesize novel optical-CT scanning systems, and novel radiochromic formulations will achieve substantial increase in speed and practicality without compromising accuracy. We also hypothesize that 3D dosimetry techniques will detect more clinical IMRT deliveries failing standard comparison metrics, than conventional 2D techniques. This proposal will conduct the first comprehensive 3D investigations of the accuracy of IMRT deliveries in cohorts of patients in key clinical sites (pelvic, head-and-neck, and thorax). Successful completion will elevate the state-of-the-art for verification of advanced radiation treatments, and may demonstrate the feasibility of a powerful and comprehensive new 3D credentialing technology with potential to elevate the standard of practice in clinical trials. There is an urgent need to improve the accuracy of advanced radiation therapy. We investigate a 3- dimensional dosimetry system that will address this need by facilitating dosimetric error detection. The first comprehensive investigations of the accuracy of dosimetry in patient treatments in 3D will be conducted.